Women who have things mansplained to them in the workplace can now report it to a dedicated hotline.

Unionen, Sweden’s largest union, is encouraging members to call up when male colleagues give them unsolicited lectures on things they already understand.

The organisation, which represents 600,000 private sector workers, launched the advice line on Monday and said it will be open from 10am to 4pm everyday for a week as part of a campaign to highlight and stamp out the insidious and damaging practice.

For those who might not be familiar with the modern portmanteau, the union defined mansplaining as when “a man explains something to a woman without being asked, particularly something which she might already know more about than the man”.

Unionen said the commonplace practice diminishes women, by making them appear less competent than they are.

A study by the American Psychological Association found that men “tend to overestimate their intelligence to a much greater extent than women” and showed that “self-assurance in men grows with age”.

Unionen said the phone line, which will be staffed by a gender expert and a group of feminist politicians, comedians and scientists, is “about equality”.

“It is about putting your finger on the small everyday problems which become large when they stack up.”

When left unchecked, mansplaining can contribute to men earning more than women, and being promoted faster, the organisation said – “something most of us, regardless of sex, think is unfair and want to change”.

The hotline will advise upset and frustrated callers on what action they should take next, and aims to help them move on. But there are no set answers, instead the people staffing the line will have the freedom to say what they want, based on their own experiences.

Nothing says equality like creating a special hotline for women to complain about their feelings.